Side pillar air curtain guide with air curtain insert having a plurality of ribs

ABSTRACT

A side pillar air curtain guide includes a main body having a ramp receiver and an air curtain ramp insert connected to the main body. The air curtain ramp receiver insert includes a plurality of ribs projecting from the main body at an acute included angle with the main body.

This application is a divisional of prior U.S. patent application Ser.No. 14/846,101 filed on Sep. 4, 2015, the full disclosure of which isincorporated herein by reference.

TECHNICAL FIELD

This document relates generally to air curtain systems for protectingvehicle occupants in side impacts and, more particularly, to a sidepillar air curtain guide incorporating a ramp for guiding the aircurtain over the center or B-pillar assembly of the vehicle.

BACKGROUND

Air curtains protecting occupants of a vehicle from side impacts arewell known in the art. Typically such systems include an air curtainguide incorporating a ramp to direct the trajectory of the inflatingcurtain so that it does not contact the upper edge of the center orB-pillar trim during deployment. This is done to minimize anypossibility of the pillar trim becoming detached and preventing thecurtain from achieving its intended “deployed” position from which itmay provide maximum safety benefit.

Side air pillar curtain guides are typically very rigid in order toprovide the desired ramp function when contacted by the rapidlyinflating air curtain. In contrast to the required strength to withstandthe initial impact and guide the inflating air curtain, the air curtainguide must also incorporate energy absorbing countermeasures in theevent of a head impact so as to minimize potential injury to a vehicleoccupant. In the past, these countermeasures have typically occupiedspace behind the headliner that drives the surface of the headliner intothe interior of the cabin compromising the interior roominess of thevehicle.

This document relates to a side pillar air curtain guide that providesthe necessary strength for properly guiding a rapidly inflating aircurtain while also providing the desired energy absorbingcharacteristics necessary to minimize head injury in the event of a headimpact. Further this is achieved in a compact structure which allows thepossibility of maximizing the interior room of the passenger compartmentof the vehicle.

SUMMARY

In accordance with the purposes and benefits described herein, a sidepillar air curtain guide is provided. The guide includes a main bodyincluding a ramp receiver and an air curtain ramp insert connected tothe ramp receiver. The main body is made from a first material having astrength S₁ and a ductility D₁. In contrast, the air curtain ramp insertis made from a second material having a strength S₂ and a ductility D₂where S₁>S₂ and D₁<D₂.

In one possible embodiment, the main body includes a ramp apron and thereceiver is adjacent to and below the ramp apron. The ramp apron has afirst air curtain guide surface and the air curtain ramp insert has asecond air curtain guide surface aligned with the first air curtainguide surface. The air curtain ramp insert complies with FMVSS201requirements for head impact.

In one possible embodiment, the air curtain ramp insert includes aplurality of ribs projecting from the main body at an acute includedangle with the main body. That acute included angle may be between 10degrees and 60 degrees. Alternatively, it may be between 30 degrees and40 degrees.

In another possible embodiment, the air curtain ramp insert includes ahoneycomb array. That array may have an X-axis or fore-aft dimension of4-7 honeycomb cells or 120-130 mm and a Y-axis or cross vehicledimension of 1-2 honeycomb cells or 20-25 mm. The honeycomb array mayalso have a Z-axis dimension or thickness of 1.5-2.5 mm. The X-dimensionis parallel to a face of the ramp receiver and the Y-dimension isperpendicular to the face of the ramp receiver. Each honeycomb cell mayhave six sides and each side may be 6 mm in length.

In still another embodiment the air curtain ramp insert includes aplurality of honeycomb arrays wherein the honeycomb arrays are separatedby gaps to insure greater deformability of the air curtain ramp insert.

In one possible embodiment, the ramp receiver includes a recess. In onepossible embodiment, the second material is closed cell rubber foam. Inyet another possible embodiment, the second material is a highperformance closed cell plastic foam.

In accordance with an additional aspect, a side pillar air curtain guideis provided that comprises a main body including a ramp receiver and anair curtain ramp insert connected to the main body. That air curtainramp insert has a honeycomb construction.

The honeycomb cells of that honeycomb construction are aligned in avertical plane when the side pillar air curtain guide insert is in anoperative position connected to the main body. Further, the honeycombcells are aligned parallel to a face of the ramp receiver.

In the following description, there are shown and described multipleembodiments of the side pillar air curtain guide. As it should berealized, the side pillar air curtain guide is capable of other,different embodiments and its several details are capable ofmodification in various, obvious aspects all without departing from theguide as set forth and described in the following claims. Accordingly,the drawings and descriptions should be regarded as illustrative innature and not as restrictive.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

The accompanying drawing figures incorporated herein and forming a partof the specification, illustrate several aspects of the air curtainguide and together with the description serve to explain certainprinciples thereof. In the drawing figures:

FIG. 1 is a front elevational view of a first embodiment of a sidepillar air curtain guide including a main body and an air curtain rampinsert.

FIG. 2 is a front elevational view of the main body of the embodimentillustrated in FIG. 1 showing the ramp receiver recess.

FIG. 3 is a perspective view of the air curtain ramp insert received inthe ramp receiver recess of the main body illustrated in FIG. 1.

FIG. 4 is a perspective view of a second embodiment of side pillar aircurtain guide including a main body and an air curtain ramp insert ofhoneycomb construction.

FIG. 5 is a top plan view of the second embodiment of side pillar aircurtain guide.

FIG. 6 is a front elevational view of the second embodiment.

FIG. 7 is a cross-section view defined by the section line A-A of theembodiment illustrated in FIG. 5.

FIG. 8 is an isometric cross-sectional view of the embodimentillustrated in FIG. 5.

FIG. 9 is another isometric view of the embodiment illustrated in FIG.4.

FIGS. 10-11 schematically illustrate the deployment of a side curtainover the air curtain guide illustrated in FIGS. 5-7.

FIG. 12 is a transverse cross-sectional view of a side curtain over theair curtain guide illustrated in FIG. 13.

FIG. 13 is a front elevational view of a third embodiment of side pillarair curtain guide, where the array is divided into three differenthoneycomb sections.

FIG. 14 is a cross-sectional view taken along section line B-B of FIG.13.

Reference will now be made in detail to the present preferredembodiments of the guide, examples of which are illustrated in theaccompanying drawings.

DETAILED DESCRIPTION

Reference is now made to FIGS. 1-3 illustrating a first embodiment ofthe side pillar air curtain guide 10. The guide 10 includes a main body12 incorporating a ramp receiver 14 in the form of a lateral recess. Anair curtain ramp insert 15 is received and held in the ramp receiver 14on the body 12. The air curtain ramp insert 15 includes a plurality ofribs 16 that project from a mounting base 17. Significantly, the ribs 16project from the base 17 and the main body 12 of the assembled guide 10at an acute and included angle so that they are characterized byenhanced deformability which provides desirable energy absorbingcharacteristics in the event of an impact with a head of a vehicleoccupant.

In one possible embodiment the acute included angle is between 10degrees and 60 degrees. In another possible embodiment the acuteincluded angle is between 30 degrees and 40 degrees. In yet anotherpossible embodiment the acute included angle is about 30 degrees.

As further illustrated, the main body 12 includes a ramp apron 18. Theramp receiver 14 is adjacent to and just below the ramp apron 18. Theramp apron 18 includes a first air curtain guide surface 20 and the aircurtain ramp insert 15 includes a second air curtain guide surface 22formed by the upper edges of the ribs 16. The two surfaces 20, 22 arealigned when the air curtain ramp insert 15 is properly seated in theramp receiver 14 and connected to the main body 12 by ultrasonic weldingor other appropriate means.

Significantly, the main body 12 is made from a first material having astrength S₁ and a ductility D₁. In contrast, the air curtain ramp insert15 is made from a second material having a strength S₂ and a ductilityD₂ where S₁>S₂ and D₁<D₂. In one possible embodiment, the main body 12is made from polycarbonate-acrylonitrile butadiene styrene (PC-ABS) andthe air curtain ramp insert 15 is made from polypropylene. In another,the air curtain ramp insert is made from closed cell rubber foam withcompressive strength between 60 kPa and 200 kPa at 25% strain. In yetanother possible embodiment, the air curtain ramp insert is made from aclosed cell plastic foam with compressive strength between 90 kPa and200 kPa at 25% strain.

Of course, it should be appreciated that other materials may beutilized. In one particularly useful embodiment, the first material fromwhich the main body 12 is made has a strength S₁ of between about 40 MPaand about 60 MPa and a ductility D₁ inherent to materials within therange specified for S1 and that are suitable for automotiveapplications. In contrast, the second material from which the aircurtain ramp insert 15 is made has a strength S₂ of between about 60 kPaand about 20 MPa and a ductility D₂, generally greater than D1. Due toInterior Head Impact requirement is not only dependable of stiffness ofthe ramp insert 15 but also dependable of the kinematics generated bythe interaction between the Free Motion Head and the vehicle interiorcomponents, the main mechanical parameter the air curtain ramp insertdefined herein must meet is energy absorption based on compressivestress from 0.25 MPa to 0.80 MPa with a compressive strain with a rangeof 0.60 to 0.75 mm/mm under a quasi-static Crush Testing.

Reference is now made to FIGS. 4-12 illustrating a second embodiment ofside pillar air curtain guide 10′ including: (a) a main body 12′ havinga ramp receiver 14′ and a ramp apron 18′ and (b) an air curtain rampinsert 15′ of honeycomb construction. Significantly, the honeycombed aircurtain ramp insert 15′ provides desirable energy absorbingcharacteristics in the event of an impact with a head of a vehicleoccupant. As in the previous embodiment described above, the air curtainramp insert 15′ is nested into the ramp receiver 14′ and ultrasonicwelded or otherwise secured to the main body 12′. When properly seated,the first air curtain guide surface 20′ of the ramp apron 18′ is alignedwith the second air curtain guide surface 22′ formed by the honeycombcells 24′ of the air curtain ramp insert 15′.

The honeycomb array of the air curtain ramp insert 15′ may have anX-axis dimension, parallel to a face 26′ of the ramp receiver 14′ andrunning in a motor vehicle fore-aft direction, of between 4-7 honeycombcells 24′ about 120-130 mm in length and a Y-axis dimension,perpendicular to the face 26′ and running in a cross vehicle direction,of 1-2 honeycomb cells about 20-25 mm in length. The honeycomb array mayhave a height or Z-axis dimension of between about 1.5-2.5 mm. Thehoneycomb cells 24′ of the honeycomb array are aligned in a verticalplane (Z-direction) when the side pillar air curtain ramp insert 15′ isin an operative position connected to the main body 12′. Each honeycombcell 24′ of the honeycomb array may have six sides 28′ and each side maybe, for example, 6 mm in length.

Reference is now made to FIGS. 10-12 illustrating the deployment of aside air curtain C over the guide 10′. As illustrated the guide 10′ ismounted to the vehicle center side pillar P (the B-pillar) between thefront and rear doors so as to overlie the pillar trim T. The undeployedside curtain C is positioned overlying the guide 10′ and both the sidecurtain C and guide 10′ are hidden from view by the headliner H. Asindicated in FIG. 11, in the event of a side impact, the side curtain Cis deployed. As the side curtain C is rapidly inflated, it engages andis guided by the guide 10′ including the first air curtain guide surface20′ of the ramp apron 18′ and the second air curtain guide surface 22′formed by the top edges of the air curtain ramp insert 15′. As should beappreciated, the ramp insert 15′ strongly resists any deflection whenengaged by the inflating side curtain C along the inclined portions ofthe top edge. Thus, the inflating curtain C is guided over the pillartrim T by the guide 10′ forcing a gap between the pillar trim T and theheadliner H through which the curtain is deployed into its functionaland desired position for maximum benefit to the vehicle occupants. Whilethe ramp insert 15′ strongly resists deflection in a vertical direction(see FIG. 12 and note action arrow A) so as to properly guide theinflating curtain C over the pillar trim T, the honeycomb cells 24′ ofthe ramp insert are very deformable in a horizontal direction (note alsoaction arrow B) so as to cushion any head impact that might occur atother times.

Reference is now made to FIGS. 13 and 14 illustrating anotheralternative embodiment of a ramp insert 15″ including the side pillarair curtain guide 10″. The guide 10″ includes a main body 12″ having aramp receiver 14″ and a plurality of honeycomb arrays 19″ held in thereceiver. In contrast to the second embodiment of the guide 10′illustrated in FIGS. 4-12, the third embodiment of guide 10″ includesfour honeycomb arrays 19″ that do not engage each other. In one possibleembodiment, the four honeycomb arrays 19″ are spaced from each other bya gap G having a width of 6.0-7.0 mm. This spacing between honeycombarrays 17″ ensures greater deformability in the horizontal direction(the Y-axis) so that the ramp insert 15″ can absorb more energy in theevent of a head impact by a vehicle occupant.

In summary, numerous benefits result from employing the illustratedembodiments of the side pillar air curtain guides 10, 10′, 10″.Significantly all three embodiments 10, 10′, 10″ incorporate a main body12, 12′, 12″ made from a first material with strength S₁ and ductilityD₁ tuned to provide desired properties for mounting the guide to theB-pillar. In addition all three embodiments 10, 10′, 10″ incorporate aramp insert 15, 15′, 15″ made from a second material tuned to providedesired properties including the necessary rigidity in the verticaldirection to receive and guide the rapidly inflating air curtain C overthe side pillar trim T so that the curtain is received in its desireddeployed position where it can protect occupants of the vehicle fromside impact. At the same time, the ramp inserts 15, 15′, 15″ providesignificant deformability in the horizontal direction so that they canabsorb energy in the event of a head impact by an occupant of a vehicle.Advantageously, the use of two different materials for the main body 12,12′, 12″ and the ramp insert 15, 15′, 15″ substantially eliminateperformance compromises and result in a better performing product. Theincorporation of the honeycomb construction into the ramp inserts 15′,15″ also allows for performance tuning to meet design goals includingFMVSS201 requirements.

The foregoing has been presented for purposes of illustration anddescription. It is not intended to be exhaustive or to limit theembodiments to the precise form disclosed. Obvious modifications andvariations are possible in light of the above teachings. All suchmodifications and variations are within the scope of the appended claimswhen interpreted in accordance with the breadth to which they arefairly, legally and equitably entitled.

What is claimed:
 1. A side pillar air curtain guide, comprising: a mainbody including a ramp receiver and a ramp apron, said ramp receiverbeing adjacent to and below said ramp apron; and an air curtain rampinsert held in said ramp receiver, said air curtain ramp insertincluding a plurality of exposed ribs projecting away from said mainbody at an acute included angle between 10 degrees and 60 degrees withsaid main body wherein said ramp apron has a first air curtain guidesurface and said air curtain ramp insert has a second air curtain guidesurface aligned with said first air curtain guide surface.
 2. The sidepillar air curtain guide of claim 1, wherein said main body is made froma first material having a strength S₁ and a ductility D₁.
 3. The sidepillar air curtain guide of claim 2, wherein said air curtain rampinsert is made from a second material having a strength S₂ and aductility D₂ where S₁>S₂ and D₁<D₂.
 4. The side pillar air curtain guideof claim 3, wherein said second material is a closed cell rubber foamhaving a compressive strength between about 60 kPa and about 200 kPa at25% strain.
 5. The side pillar air curtain guide of claim 3, whereinsaid second material is a high performance plastic foam with acompressive strength between about 90 kPa and about 200 kPa at 25%strain.
 6. The side pillar air curtain guide of claim 1, wherein saidmain body is made from a first material having a strength S₁ and aductility D₁.
 7. The side pillar air curtain guide of claim 6, whereinsaid air curtain ramp insert is made from a second material having astrength S₂ and a ductility D₂ where S₁>S₂ and D₁<D₂.
 8. The side pillarair curtain guide of claim 7, wherein said second material is a closedcell rubber foam having a compressive strength between about 60 kPa andabout 200 kPa at 25% strain.
 9. The side pillar air curtain guide ofclaim 7, wherein said second material is a high performance plastic foamwith a compressive strength between about 90 kPa and about 200 kPa at25% strain.
 10. A side pillar air curtain guide, comprising: a main bodyincluding a ramp receiver and a ramp apron, said ramp receiver beingadjacent to and below said ramp apron; and an air curtain ramp insertheld in said ramp receiver, said air curtain ramp insert including aplurality of exposed ribs projecting away from said main body at anacute included angle between 30 degrees and 40 degrees with said mainbody wherein said ramp apron has a first air curtain guide surface andsaid air curtain ramp insert has a second air curtain guide surfacealigned with said first air curtain guide surface.